Drill



M. HOFFMAN AND P. JOPLING.

s. L. ZERBA, ADMINISTRATRIX or P.10PLING. ozc'n.

DRILL. 'APPLICATION FILED JUNE 17, I916- RENEWED JULY 21,1919. ,458,

A TTORIVEYS M. HOFFMAN AND F. JOPLING. I s. L. ZERBA, ADMINISTRATRIX OF P. JOPLING. nsc'o.

DRILL.

APPLICATION FILED JUNE I7, 1916. RENEWED JULY 21.1919.

1,331,458. Patented Feb. 17,1920.

-3 SHEETS-SHEET 2- ,j/lll w B y 05064850.

A TTORNE V8 M. HOFFMAN AND P. .IOPLING. S. L- ZERBA, ADMI NISTRATRIX OF P. JOPLING. DEC'D DRILL.

APPLICATION FILED JUNE I7, '1916- RENEWED JULY 2|,- l 9l 9- 1,331,458, 7 Patented Feb. 17,1920.

3 SHEETS-SHEET 3.

WITNESSES.-

A TTOHIVEYS srATns PATENT OFFICE.

MARGUERI'IE HOFFMAN, OF ROCK ISLAND, ILLINOIS, AND IEARSON J OPLING, DECEASED, LATE OF ROCK ISLAND, ILLINOIS, BY SARAH L. ZERBA, ADMINIS- TRATR-IX, OF ROCK ISLAND, ILLINOIS.

DRILL.

Application filed June 17, 1916, Serial No. 104,339. Renewed July 21, 1919.

To all whom it may concern:

Be it known that we, MARGUERITE Horr- MAN, a citizen of the United States, and a resident of Rock Island, in thecounty of Rock Island and State of Illinois, and PEARSON JOPLING, deceased, a late citizen of the United States, and a late resident of Rock Island, in the county of Rock Island and State of Illinois, have invented new and useful Improvements in Drills, of which the following is a specification.

The invention is an improvement in drills, and has for its object to provide a novel form of drill head, wherein oppositely arranged longitudinally extending guide ribs are provided for guiding the drillings to the drive worm, said ribs forming -continuations of the ribs of the worm and having shoulders butting the ends of the ribs, and wherein a novel form of bit is provided formed'irom a plate of metal stampedand bent to shape, and so connected with the head that it will be firmly held and braced for cutting movement.

In the drawings I Figure 1 is a perspective view of the head, bit and drive worm detached,

Fig. 2 is a partial perspective ing the connection between the and the bit,

Fig. 3 is a bottom plan view, Q

Figs. 4:, 5 and 6 are sections on the lines H, 5-5 and 6-6, respectively, 01": Fig. 2, Fig. at lookin in the direction of the arrows adjacent to the line, I

Fig. 7 is a top plan view of a blank for a modified construction of bit,

Fig. 8 is a front view of the bit formed from the blank shown in Fig. 7 in place in the drill head, v

Fig. 9 is an end view of the drill head looking r'rom below,

Fig. 10 is a similar view looking 'l rom above, v V

Fig. 11 is an end view of the bit looking from above, I

Fig. 12 is an end view looking from below,

Fig. 13 is an end view looking "from above of the modified form of head shown in Fig. 15,

view showdrive worm Specification of Letters Patent.

of bit formed from Patented Feb. 17, 1920.

Serial No. 312,320.

gig. 1a is a similar view from the other en Fig. 15 is a perspective view of the drill head,

Fig. 16 is an end view of a modified form the blank shown in Fig. 18,

Fig. 17 is end, and

Fig. 18 is a plan view of the blank from which the. bit is formec.

In the embodiment of the invention shown in Figs. 1 to 6, there is shown a drive worm formed from a strip of metal, and comprising a spirally twisted body 1, having at each end a tongue 2 and 3, respectively. The tongue 2 is adapted for connection with the operating mechanism for the drill, and the tongue 3 for connection with the drill head a. This tongue 3 as shown, is reduced at each side to form ashoulder 5 at each side of the tongue between the same and the body of the drive worm, and the shoulders 5 are connected at the opposite faces of the tongue by shoulders 6 which extend across the drive worm at the junction of the tongue and body. This tongue 3 is adapted to enter a longitudinally extending similarly shaped recess 7 in the body of the drill head 4., and the shoulders 6 and 5 engage the drill head to limit the inward movement of the tongue with respect to the head.

A. set screw 8 is threaded through openings of the head transversely of the recess 7, and the tongue 3 has an opening 9 for permitting the passage of the screw to rig; idly connect the drive worm to the head. It will be noticed from an inspection of the drawings that the head 4t is provided at each side edge and on opposite faces with lateral ribs 10, the said ribs extending longitudinally of the head, and each rib has its inner face concave as shown. These ribs are similar but oppositely arranged, and they are guide ribs for guiding the detritus from the drill hole to the drive worm.

It will be noticed from an inspection of Figs. 1 and 2 that each guide rib 10 is extended beyond the upper end of the drill head and that a square shoulder 11 is formed a similar view from the other between the inner or connected edge of each tending central the concave faces of the rib and the upper face of the head. When the tongue 3 of the drive worm is inserted in therecess '7 the spiral ribs of the drive worm will butt'up against these ribs 11 so that the guide ribs 10 will be in elfect continua-tions of the spiral ribs of the drive worm.

The material cut by the bit to be later Tl described, will move along the concave faces of these guide ribs 10 to the spiral ribs of the drive worm, and will be removed from the openings by the spiral ribs. The guide ribs are in effect feedribs for the ribs of the drive worm. The head is also provided on each face with a longitudinally eX- guide rib 12, the said ribs being parallel with the ribs 10 and spaced aparttherefrom, and the said ribs are not directly opposite each other but are offset or staggered as shown more particularly in Figs. 3 and 4. These ribs 12 extend to the cut-away upper end of the head, being of less length than the lateral ribs 1 In use when the head is turned by means of the drive worm 1, the lower endsof the spiral ribs of-the worm will bear against the shoulders 11 so that there will be no possibility of twisting or angular movement of the worm with respect to the head. The drillings which are always confined to the left side of the drill head will be forced up ribs 10 and up the channel formed betweenfthe ribs 10' and 12 to the spiral ribs of the drive worm, which will remove them from the drill hole.

The lower end of the drill head is provided with a slot 13 for receiving the shank of the bit to be later described, and this slot as shown clearly in Fig. 6, has-its bottom wall convex at the center of the slot and concave near each end, and the shank of the bit is shaped to fit this concavo-convex bottom wall. The bit as shown in Figs. 1 and 3, is formed from a plate of suitable material which is stamped to form blank, which is afterward bentto' shape. The bit has a plane shank portion 14 of approximately triangular outline, the bore being adapted to enter the slot or passage 13 and being shaped tofit the 'concavo-convex bottom wall 13 of the saidslot or passage, and wings 15 and 16 at each side of the body, the said wings being also of approximately triangular outline as shown.

At the outer or cutting end the blank is notched at each corner as indicated at 17, thesaid notches being between the wings 15 and '16 at each side. These wings 15 and 16 at each side of the body 14 have their bases outward and those portions of the wings near the bases are bent in opposite directions as clearly shown in Fig. 3, the bent portions being curved as shown. Thus the outer corners of the wings l5 and 16 form it 8, which is blank may be considered cutting teeth, and the bases of the portions meet. at an obtuse angle as shown to form a cutting point at the center, of the cutting edge of the bit. I

The bit is held in place in the slot or passage of the head by means of a screw or pin passed through registering openings in the head and in the shank of the bit. 1e concave-convex outline of the bottom of the slot or passage 13 and the correspond ingly shaped edge of the base at the body of the bit provide a means for preventing rocking movement of the bit with respect to the head. T'

In Fig. 7 is shown a blank in a modified form of bit. \Vith this arrangement the as composed offive triangles in theflsame manner, as the blank shown in Fig. 1, namely, a body;19' of triangular form and wings 20 and 21' also of triangular form. The'base ofthe body 19 is designedto engage the passage 13: of the head and this portion of the bit is plane. The wing. 20. has its base outward and at the outer angle each wing 20 is notched as shown at 22.

The wings 21 have their bases inward, and

these wings 20 and 21 of each side are approximately right-triangles. "When the blank is bent on the lines separating the wing 19 from the wings 20, the inner walls of the notches 22 will form teeth in the same manner as the, innerwa-lls of the notches 17. The wings. 20 and 21 arebent in opposite directionsfin th same manner as shown in Fig. 3.

In Figs 8, to 12, the head 23is similar toengaged by holding means which are passed through oppositely arranged openings 28 in the head, and the upper end of the head is provided with a slot or passage 29, corresponding to the slot or passage 13, shown in Figs. 1 to 6 for receiving the shank of the bit, and the bottom wall of the slot or passage is concavo-convex like the bottom wall of the slot or passage 13.

The bit shown in Figs. 8, 11 and 12, comprises a body 30 of approximately triangular outline and having its base shaped to fit the bottom-wall of the passage 29, wings 31 and 32iat each side of the body, and a wing 33 at the base of the'wing 31. hese wings 33 are limited by lines passing from the apex of the body 30 to the inner corners of the notches 34. The bases ofthe wings 31 and 32 and the wings 33 are bent in opposite directions as shown in Figs. '11 and 12. It will be understood that the limiting lines between the wings and between the wings and the body are not found in practice, being merely describedfor convenience, the wings merging gradually into each other.

In Figs. 13 to 15 is shown a modified form of drill head, the head comprising a substantially cylindrical body 35, having oppositely arranged spiral ribs 36. The drill head is provided at one end with a recess 37 for receiving the tongue 3 of the drive worm, and the opposite end of the head is tapering or frusto-conical as shown, and is provided with a transverse slot or passage.

88 for receiving the shank of the bit. This passage as will be evident from an inspection of Fig. 15, has its ends at the terminations of the lbs 36, so that when the bit to be later described, is within the slot or passage the corners of the shank will be practically continuations of the ribs 86.

The bit is formed from the blank shown in Fig. 18, the said blank being an approximately rectangular plate 39, having however, the corners at one edge notched deeply as indicated at 410. The blank may be considered as being composed of a body triangular in outline whose base is shaped to fit the bottom of the passage or slot 38, and a wing at each side of the body, the notches 40 being at the outer angles of the substantially triangular wings. The wings are bent in opposite directions in the same manner as the wings 15 and 16 of Fig. 1, the inner walls of the notches 40 forming cutting teeth. The center guide wings 12 of Figs. 3 and at are for the purpose of causing the drill to drill straight, preventing it from veering to one side and insuring a straight drill hole. This is of great advantage as it permits the explosive to pass to the extreme end of the hole in a more uniform manner, and the explosive is not strung out.

The wings 21 of the bit shown in Fig. 7 are for the purpose of preventing the drillings from falling into the hole back of the drill head and bit, at the point where the drill bit fits down in the recess and up against the drill head. In each construction two screws 53 are provided engaging in 0pposite directions, for holding the bit firm in the upper part of the drill head.

W's claim 1. A drill head having at each side edge a guide rib, said ribs extending laterally from opposite faces and opposite edges of the head and from one end of the head to the other, andbeing concave on their inner faces, the head having a central guide rib on each face adjacent to each lateral rib, and having a recess in one end for receiving a drive worm, the lateral ribs being extended beyond the said end of the head and abutting against the ribs of the worm.

2.. In combination drill head having at one end a transversely extending slot, the bottom of the slot beingconvex intermediate its ends and concave at each end, and a bit having a shank adapted to enter the slot and shaped to fit the bottom thereof, said bit and head having registering openings, and a pin passing through the openings for connecting them together.

3. In combination a drill head having at one end a transversely extending slot, the bottom of the slot being convex intermediate its ends and concave at each end, and a bit having a shank adapted to enter the slot and shaped to fit the bottom thereof.

4. In combination a drill head having at one end a transversely extending slot, the bottom of the slot being convex intermediate its ends, and a bit having a shank adapted to enter the slot and shaped to fit the bottom thereof.

5. In combination, a drill head having a slot provided with a convex bottom wall, and a bit having one end plane and shaped to [it the convex bottom of the slot, the opposite end being notched at each corner, and the corners being bent in opposite directions, said head having a longitudinal outwardly extending guide rib at each face of the bit, and the corners of the bit being bent in the same direction as the ribs.

6. In combination, a drill head having a slot provided with a convex bottom wall, and a bit having one end plane and shaped to fit the convex bottom of the slot, the opposite end being notched at each corner, and the corners being bent in opposite directions.

7. In combination, a drill head having a slot provided with a convex bottom wall, and a bit having one end plane and shaped to fit the convex bottom of the slot.

8. In combination with the driving worm having spiral ribs, a drill head having longitudinal ribs at the opposite side edges and at opposite faces of the head, and having a recess in one end for receiving the drive worm having spiral ribs and having a tongue fitting the recess of the head, the ribs of the head having shoulders butting against the ends ofthe ribs of the worm.

9. In combination with the driving wormv having spiral ribs, a drill head having longitudinal ribs at the opposite side edges and at opposite faces of the head, the ribs of the head having shoulders butting against the ends of the ribs of the worm.

10. A drill bit formed from a substantially rectangular plate of metal having one edge concave and having its corners notched, the corners remote from the concave edge being curved in opposite directions, and the said edge consisting of two portions extending at an obtuse angle with respect to each other from the center of the edge.

11. A drill bit formed from a substantially rectangular plate of metal having one --edge concave and having the corners at the opposite edge notched, the said corners belng curved in opposite directions.

'12. A drill. bit formed from a substantially rectangular plate of metal having the corners at one edge notched, and the said corners being curved in opposite directions.

13. A drill 'bit formed from a substantially rectangular plate of metal having one 1 edge concaved and having the'cornersat the opposite edge .curvedin opposite directions.

MARGUERITE HOFFMAN. SARAH L. ZERBA V A dmlz'm'stmtmx 0 fiPe arson 'J 0 p Zmg, deceased.

Witnesses t0 s1gnatures- ARTHUR R. BLENER, A. C; LEI-DEL. 

